Navien NCB-150E Installation & Operation Manual page 24

Before connecting the condensate drain, choose one of the
following disposal options:
a. From the boiler directly into an external drain
b. From the boiler, through a neutralizing agent, and then
into an external drain
If you choose this option, the neutralizing agent
Note
must be replaced periodically. Depletion of
the neutralizing agent will vary, based on the
usage rate of the boiler. During the first year of
operation, the neutralizer should be checked
every few months for depletion and replaced as
needed.
c. From the boiler into a laundry tub.
The bottom of the boiler must be higher than
Note
the top of the laundry tub to use this option. The
condensate line must have a negative slope to
drain properly.
d. From the boiler into a condensate pump, and then into a
laundry tub.
A pump can be used when there is a long
Note
distance between the boiler and the laundry tub
or when the bottom of the boiler is lower than the
top of the laundry tub.
24 Installing the System Piping
To connect the condensate drain:
1. Connect a drain line to the
boiler.
Use only corrosion-resistant material for the drain line, such as
PVC or CPVC. Do not reduce the size of this fitting or the drain
/
1
line to less than in.
2
2. Place the free end of the drain line into an appropriate drain.
3. If you are using a condensate pump, ensure that the pump
allows for up to 2 GPH of drainage for each boiler in the
system.
4. If you are not using a condensate pump, ensure that the drain
line is pitched downward at a minimum slope of
/
1 in fitting at the bottom of the
2
NPT 1/2 in
/
1 in per foot.
4